The invention can be advantageously used to search, guide and track objects within the field of view of a scanning raster line. It can be employed in systems intended to analyse the structures of complex half-tone images of various micro- and macro-objects. In particular, it can be used in astronomy to automatically track stars and planets; in biology, to perform selective search of individual objects for their detailed analsyis on the basis of the parameters of their images; in metallography, to analyse the structures of polished specimens; in medicine, to study various objects, such as cytology preparations for their analysis. In addition, it can be used to solve other applied and scientific problems where it is required that the process of successively selecting images of objects and passing them to a measurement or identification system should be automatic.
Included in the prior art is a device which selectively searches for and tracks an object using its image and which comprises a video pickup, a photoelectric scanner, a video signal processor and a servomechanism to displace the video pickup with respect to the image being searched.
This device comprises an optical telescope aimed at a celestial body. The image of the celestial body is focused optically on a photoelectric scanner that converts the image into a series of pulses whose time of generation determines the distance between the fixed coordinate axis and the circumference of the celestial body's image. Then, the pulses are differentiated and the resulting signals are fed to a computer which calculates the coordinates of the center of the celestial body.
A drawback of the known device lies in that its application is rather limited since it is preprogrammed to solve a single specific proble, viz, as a horizon sensor, to find the vertical to a partially darkened plant. Hence, the device cannot be used to selectively search for an object whose image is against the background of a random set of mixed objects having different contrasts, chromaticities and geometric sizes. Nor can it be used in systems requiring that images of objects should be automatically passed in succession for further analysis, since to have a system track an object it is necessary to manually pre-aim the optical means of the device at the object.